The six species currently classified within the genus Lagenorhynchus exhibit a pattern of antitropical distribution common among marine taxa. In spite of their morphological similarities they are now considered an artificial grouping, and include both recent and the oldest representatives of the Delphinidae radiation. They are, therefore, a good model for studying questions about the evolutionary processes that have driven dolphin speciation, dispersion and distribution. Here we used two different approaches. First we constructed a multigenic phylogeny with a minimum amount of missing data (based on 9 genes, 11,030 bp, using the 6 species of the genus and their closest relatives) to infer their relationships. Second, we built a supermatrix phylogeny (based on 33 species and 27 genes) to test the effect of taxon sampling on the phylogeny of the genus, to provide inference on biogeographic history, and provide inference on the main events shaping the dispersion and radiation of delphinids. Our analyses suggested an early evolutionary history of marine dolphins in the North Atlantic Ocean and revealed multiple pathways of migration and radiation, probably guided by paleoceanographic changes during the Miocene and Pliocene. L. acutus and L albirostris likely shared a common ancestor that arose in the North Atlantic around the Middle Miocene, predating the radiation of subfamilies Delphininae, Globicephalinae and Lissodelphininae. (C) 2014 Elsevier Inc. All rights reserved.
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledgements: This project was supported by the Programme Alban, European Union Programme of high level Scholarship for Latin America (Identification number EO3D17203CO); The Alexander von Humboldt Biological Resources Research Institute (as the supporting entity for the Alban scholarship), the Colombian Institute of Studies Abroad (ICETEX), the United Nations Environmental Programme/Agreement on the Conservation of Small Cetaceans of the Baltic, North East Atlantic, Irish and North Seas (UNEP/ASCO-BANS); the School of Biological and Biomedical Science and Ustinov College, University of Durham. We acknowledge SWFSC for providing samples (Z-27494, Z-47653, Z-8261, Z-8273, Z-8250, Z-8268). We thank Kelly Robertson from (NOAA), Robert Suydam (North Slope Borough in Alaska), Alaska subsistence hunters, Dr. Mads Peter Heide-Jorgensen (Greenland Institute of Natural Resources), the Center for Marine environmental studies at Ehime University, Bob Reid, Mary Harman (Scottish stranding network), Centro Nacional Patagonico (CENPAT) and George Gkafas for providing further samples for this study. We thank Shinsuke Tanabe, Charlie Shaw, Theresa Mackinven and Fernando Gast Harders for assistance and support, and Peter Evans and Bill Perrin for critical reviews of the manuscript.